Temp Guage Failure

I recently got the bearings done on the VX and can now drive around comfortably without the rattle.
Unfortunatley when I picked up the car, the guy asked if the temp guage was working when I left it in?
It's at this point that that little voice inside your head starts yelling.

Well it turns out that he thought that he had somehow managed to screw up the Water temp sensor, but couldn't figure out why when the terminal was removed, the car indicated a failure of the sensor,
and why the guage didn't function when the terminal was replaced.
I asked about this some weeks ago and was told that there were two temp sensors.
I can't locate the second sensor.
Could someone tell me where it is and what the part number is?
Or if they know why the temp guage should suddenly fail?

I would appreciate the help.
Thanks

The only ECT sensor is on top of the front water manifold - a hard failure will throw a P0177 or P0118.

The sensors under the intake manifold (can only be accessed with the intake off) are the knock sensor and camshaft position sensor.

You might want to download the workshop CD (must burn to a CD after download) and you can find all sorts of useful troubleshooting and service info.